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Abstract

Human evolutionary scholars have long supposed that the earliest stone tools were made by the genus Homo and that this technological development was directly linked to climate change and the spread of savannah grasslands. New fieldwork in West Turkana, Kenya, has identified evidence of much earlier hominin technological behaviour. We report the discovery of Lomekwi 3, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment. The Lomekwi 3 knappers, with a developing understanding of stone’s fracture properties, combined core reduction with battering activities. Given the implications of the Lomekwi 3 assemblage for models aiming to converge environmental change, hominin evolution and technological origins, we propose for it the name ‘Lomekwian’, which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.

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At a glance

Figures

Map showing relation of LOM3 to other West Turkana archaeological site complexes.

Figure 2: LOM3 lithological context.

a, View of the excavation, facing east, showing relationship between surface, slope deposit, and in situ contexts containing the artefacts and fossils. Scale in midground is 20 cm. Lower-leftmost artefact is the anvil LOM3-2012-K18-2, shown in Fig. 5a. b, Topographic profile and stratigraphic units at site level showing the excavation zone (Ex), the geological trench made at the base of the section (GP); the artefacts and fossils derive from a series of lenses of sand and granules making up a ~1 m thick bed (Ch). c, Section at the excavation along bands I and J (indicated by the black line in Extended Data Fig. 1a) showing the sediments which form the fan deposits containing the artefacts.

Figure 3: Chronostratigraphic framework for LOM3.

a, Chronostratigraphic framework for LOM3 (star) with generalized stratigraphic columns and magnetostratigraphic alignment to the geomagnetic polarity time scale (GPTS) in context of dates of tuffaceous markers (± 1 s.d.) and stratigraphic nomenclature for Members of the Nachukui Formation26, 30. A linearly interpolated date of 3.3 Ma for the in situ stone tools is consistent with the site’s magnetostratigraphic position within the reverse polarity interval that is correlated to reverse subchron C2An.2r (Mammoth Subchron) dated at 3.33–3.21 Ma31. b, Photograph facing north showing geographic and stratigraphic relationship between Toroto Tuff, paleobeach, and LOM3.

a, In situ passive element/anvil (LOM3-2012-K18-2, 12 kg). b, Passive element/anvil (LOM3-2012 surf 60, 4.9 kg). Both anvils a and b exhibit similar patterns of macroscopic wear consisting of superposed step fracturing in association with crushing and impacts marks. On a, damage is localized on a single lateral face, with battering marks present on one horizontal plane. On b, damage is distributed along a greater portion of the perimeter, but in this case no percussive marks are identifiable on the horizontal plane. In both cases, the intensity of the observed wear signature indicates a use in heavy-duty activities. c, Unifacial core (LOM3-2012 surf 90, 4.74 kg), bipolar technique and semi-peripheral exploitation. Inset shows crushing marks on the proximal surface of the cobble related to battering activities before or after the knapping of the core. See Supplementary Information part F for three-dimensional scans of lithic artefacts.

Extended Data Fig. 1: Map and schematic section at LOM3.

a, Map showing xy coordinates of artefacts and fossils recovered in situ and from the surface at the site in 2011 and 2012. b, Schematic section showing vertical distribution of in situ artefacts and those located in the slope deposit at the excavation. Key is the same for both figures.

Together with the technological analysis of the archaeological material, our replication experiments suggest that the LOM3 knappers were using passive hammer technique, in which the core, usually held in both hands, is struck against a stationary object that serves as the percussor34 (also referred to as on-anvil, block on block or sur percuteur dormant35) and/or bipolar technique, in which the core is placed on an anvil and struck with a hammerstone34. a, Unifacial passive hammer cores. Left is archaeological piece LOM3-2012 surf 106 (2.04 kg); right is experimental piece Expe 55 (3.40 kg) produced using the passive hammer technique. Selection of relatively flat blocks with natural obtuse angles. The flake removal process starts from a slighly prominent part of the block (white arrows show the direction of removals). The removals tend to be invasive. The flaked surface forms a semi-abrupt angle with the platform surface. A slight rotation of the block ensures its semi-peripheral exploitation. b, Unifacial bipolar cores. Left are archaeological pieces LOM3-2012-H18-1 (left, 3.45 kg) and LOM3-2012 surf 64 (right, 2.58 kg); right are experimental pieces Expe 39 (left, 4.20 kg) and Expe 24 (right, 2.23 kg) produced using the bipolar technique. The block selected are thicker and more quadrangular in shape with natural angles ≈90°. Flakes are removed from a single secant platform (white arrows show the direction of removals). The flaked surface forms an abrupt angle with the other faces of the block. Impacts due to the contrecoups (white dots) are visible on the opposite edge from the platform.

Extended Data Table 3: Comparison of anvils and percussors dimensions found at LOM3 site with anvils and percussors used by non-human primates in Bossou (wild chimpanzees, Pan troglodytes verus from ref. 41)

Extended data figures and tables

Extended Data Figures

a, Map showing xy coordinates of artefacts and fossils recovered in situ and from the surface at the site in 2011 and 2012. b, Schematic section showing vertical distribution of in situ artefacts and those located in the slope deposit at the excavation. Key is the same for both figures.

Together with the technological analysis of the archaeological material, our replication experiments suggest that the LOM3 knappers were using passive hammer technique, in which the core, usually held in both hands, is struck against a stationary object that serves as the percussor34 (also referred to as on-anvil, block on block or sur percuteur dormant35) and/or bipolar technique, in which the core is placed on an anvil and struck with a hammerstone34. a, Unifacial passive hammer cores. Left is archaeological piece LOM3-2012 surf 106 (2.04 kg); right is experimental piece Expe 55 (3.40 kg) produced using the passive hammer technique. Selection of relatively flat blocks with natural obtuse angles. The flake removal process starts from a slighly prominent part of the block (white arrows show the direction of removals). The removals tend to be invasive. The flaked surface forms a semi-abrupt angle with the platform surface. A slight rotation of the block ensures its semi-peripheral exploitation. b, Unifacial bipolar cores. Left are archaeological pieces LOM3-2012-H18-1 (left, 3.45 kg) and LOM3-2012 surf 64 (right, 2.58 kg); right are experimental pieces Expe 39 (left, 4.20 kg) and Expe 24 (right, 2.23 kg) produced using the bipolar technique. The block selected are thicker and more quadrangular in shape with natural angles ≈90°. Flakes are removed from a single secant platform (white arrows show the direction of removals). The flaked surface forms an abrupt angle with the other faces of the block. Impacts due to the contrecoups (white dots) are visible on the opposite edge from the platform.

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Additional data

Extended Data Figure 1: Map and schematic section at LOM3.

Hover over figure to zoom

a, Map showing xy coordinates of artefacts and fossils recovered in situ and from the surface at the site in 2011 and 2012. b, Schematic section showing vertical distribution of in situ artefacts and those located in the slope deposit at the excavation. Key is the same for both figures.

Together with the technological analysis of the archaeological material, our replication experiments suggest that the LOM3 knappers were using passive hammer technique, in which the core, usually held in both hands, is struck against a stationary object that serves as the percussor34 (also referred to as on-anvil, block on block or sur percuteur dormant35) and/or bipolar technique, in which the core is placed on an anvil and struck with a hammerstone34. a, Unifacial passive hammer cores. Left is archaeological piece LOM3-2012 surf 106 (2.04 kg); right is experimental piece Expe 55 (3.40 kg) produced using the passive hammer technique. Selection of relatively flat blocks with natural obtuse angles. The flake removal process starts from a slighly prominent part of the block (white arrows show the direction of removals). The removals tend to be invasive. The flaked surface forms a semi-abrupt angle with the platform surface. A slight rotation of the block ensures its semi-peripheral exploitation. b, Unifacial bipolar cores. Left are archaeological pieces LOM3-2012-H18-1 (left, 3.45 kg) and LOM3-2012 surf 64 (right, 2.58 kg); right are experimental pieces Expe 39 (left, 4.20 kg) and Expe 24 (right, 2.23 kg) produced using the bipolar technique. The block selected are thicker and more quadrangular in shape with natural angles ≈90°. Flakes are removed from a single secant platform (white arrows show the direction of removals). The flaked surface forms an abrupt angle with the other faces of the block. Impacts due to the contrecoups (white dots) are visible on the opposite edge from the platform.

Dimensions are in mm, Mass in g. *Denotes significant difference with LOM3 (t-test, one-tailed, P < 0.0001). Given the small sample sizes and potential non-normal nature of stone tool measurements, a non-parametric test such as Mann–Whitney would be preferable, but this would require access to the raw measurement data from the other Oldowan sites, access to which is currently beyond the scope of this work. The Student's t-test is very robust, however, as deviations from normality do not affect it very much, and it is currently the only option when working with published data summaries.

†The summary data from this publication was not in the correct format for direct comparison with LOM3, so information for this table was provided directly by the author in the form of personal communication.

§Dimensions of accidentally produced flakes from chimpanzee nut-cracking activity are included here for comparative purposes, although a direct technological comparison would be inappropriate as those pieces are not the result of intentional flake manufacture and do not bear the classic technological flake characteristics like those from LOM3 and early Oldowan sites.

Extended Data Table 3: Comparison of anvils and percussors dimensions found at LOM3 site with anvils and percussors used by non-human primates in Bossou (wild chimpanzees, Pan troglodytes verus from ref. 41)

Hover over figure to zoom

Dimensions are in cm, Mass in g. *Denotes significant difference with LOM3 (t-test, two-tailed, P < 0.0199). Given the small sample sizes and potential non-normal nature of stone tool measurements, a non-parametric test such as Mann–Whitney would be preferable but this would require access to the raw measurement data from ref. 41, access to which is currently beyond the scope of this work. The Student’s t-test is very robust, however, as deviations from normality do not affect it very much and it is currently the only option when working with published data summaries.

When Louis Leakey and colleagues found stone tools associated with early human fossils (now accepted to be 1.8 million years old) at Olduvai Gorge in Tanzania more than 50 years ago, it was assumed that tool-making was unique to our genus. Since then the antiquity of tool-making has gone ever deeper and less exclusively associated with Homo. For a while, the earliest-known sharp-edged stone tools, at around 2.6 million years old, have been from Ethiopia. Cut marks found on animal bones from Ethiopia dated to around 3.3 million years ago were — controversially — associated with tool use among non-human hominins. This earlier beginning to the archaeological record is now affirmed by the discovery reported by Sonia Harmand et al. of the Lomekwi 3 tools, dated to 3.3 million years old, about half a million years older than the current earliest known (2.8 million years old) Homo fossils, reported a few weeks ago. The new finds differ from the 'Oldowan' tools found at Olduvai and elsewhere, and may constitute a pre-Homo tool culture, which the authors suggest calling the 'Lomekwian'.